Significant increases in the steady states of putrescine and spermidine/spermine N1-acetyltransferase mRNA in HeLa cells accompanied by growth arrest.
Polyamines are intrinsic polycations which play critical roles in cell proliferation. Ornithine decarbolylase (ODC) catalyzes the first step of polyamine biosynthesis converting ornithine to putrescine. In addition to polyamine degradation, spermidine/spermine acetyltransferase (SSAT) regulates interconversion pathway of spermine and spermidine to putrescine. We quantified the polyamines and mRNAs of ODC and SSAT in HeLa S3 cells at various stages during exponential and plateau phases of culturing. Unexpectedly, putrescine and SSAT mRNA levels increased remarkably at the plateau phase, in contrast to the decrease of ODC mRNA level. It will be suggested that the putrescine has a novel function linked to the arrest of cell growth in which the SSAT-mediated pathway producing putrescine takes part.
Ichimura
S
S
Department of Biology and Oncology, National Institute of Radiological Science, Chiba-shi, Japan.
Hamana
K
K
Nenoi
M
M
D000123:Acetyltransferases / Q000235:genetics*; D002455:Cell Division / Q000502:physiology; D004247:DNA / Q000032:analysis; D005786:Gene Expression Regulation / Q000235:genetics*; D006367:HeLa Cells / Q000201:enzymology / Q000378:metabolism*; D006801:Humans; D009955:Ornithine Decarboxylase / Q000378:metabolism; D011073:Polyamines / Q000378:metabolism*; D011700:Putrescine / Q000378:metabolism; D012322:RNA Precursors / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D013095:Spermidine / Q000031:analogs & derivatives / Q000378:metabolism; D013096:Spermine / Q000031:analogs & derivatives / Q000378:metabolism; D000099228:Diamine N-Acetyltransferase
D000123:Acetyltransferases; D004247:DNA; D009955:Ornithine Decarboxylase; D011073:Polyamines; D011700:Putrescine; D012322:RNA Precursors; D012333:RNA, Messenger; D013095:Spermidine; D013096:Spermine; D000099228:Diamine N-Acetyltransferase; C017988:N(1)-acetylspermidine; C029452:N'-acetylspermine